How has the court treated testimony by a police officer in a civil case?

It appears from the several pages of discussion of the propriety of this 'rebuttal' testimony by the officer, that the trial judge did not truly weigh the relevancy of the testimony in light of the proffered stipulation against its highly prejudicial nature, but rather admitted it because the defendant had opened the door by first offering evidence of his lack of financial need. But this so called opening of the door does not support the introduction of this evidence. (People v. Davis, Supra, 233 Cal.App.2d 156, 43 Cal.Rptr. 357.)